Bedlam
late Middle English: early form of Bethlehem, referring to the hospital of St Mary of Bethlehem in London, used as an institution for the insane.
wiktionary
From Bedlam, alternative name of the English lunatic asylum, Bethlem Royal Hospital (royal hospital from 1375, mental hospital from 1403) (earlier St Mary of Bethlehem outside Bishopsgate, hospice in existence from 1329, priory established 1247), since used to mean “a place or situation of madness and chaos”. Bedlam as name of hospital attested 1450.
Phonologically, corruption of Bethlem, itself a corruption of Bethlehem (the Biblical town), from Ancient Greek Βηθλεέμ(Bēthleém) from Biblical Hebrew בֵּית לֶחֶם (bêṯ leḥem, literally “house of bread”).
etymonline
bedlam (n.)
"scene of mad confusion," 1660s, from colloquial pronunciation of "Hospital of Saint Mary of Bethlehem" in London, founded 1247 as a priory, mentioned as a hospital 1330 and as a lunatic hospital 1402; it was converted to a civic lunatic asylum on dissolution of the monasteries in 1547. It was spelled Bedlem in a will from 1418, and Betleem is recorded as a spelling of Bethlehem in Judea from 971. The proper name might be caught in transition in the title of John Davies' 1617 publication of humorous poetry, "Wits bedlam —where is had, whipping-cheer, to cure the mad."